Last week, Hurricane Helene traversed up the Gulf of Mexico, far enough away from Sanibel to prevent severe wind damage, but large and strong enough to produce a significant storm surge that affected many recovering wetlands nearly two years post-Ian.

“Although not a complete island-wide washover like Ian, the surge certainly brought saltwater back into many of the areas that were close to being considered recovered,” said SCCF Wildlife & Habitat Management Director Chris Lechowicz. “So far, we have not seen the evident wildlife mortality as we did immediately after Ian, but it is early.”

The freshwater wetlands on Sanibel experienced severe saltwater inundation from Hurricane Ian in September of 2022.

“It had been decades since all or most of these waterbodies had been stressed in this manner,” said Lechowicz.

History Repeats Itself

The last two storms that had severe surge events occurred in 1921 and 1926, similar to Hurricane Ian. There were two other hurricanes in 1947 and 1960 with storm surge events, but they were not island-wide and were considered minor.

Wildlife populations of many taxa increased in number and expanded their ranges to other parts of the island during the stretch of little to no severe storm surge events and flooding of the land.

“As we know from Sanibel’s history, eventually an event does occur, that may either reduce or eliminate species that depend upon freshwater to survive,” said Lechowicz.

These events are considered natural because Sanibel is a barrier island, which serves as the first land area typically impacted by most hurricanes.

“Approximately 100 years later, we experienced Hurricane Ian that washed over the island, inundating most of the waterbodies and leaving Gulf soils on our island habitats,” he said. “Species dependent on freshwater, such as various gamefish, frogs, turtles, and others experienced major losses.”

The following long dry winter without much rainfall made the situation more severe. Over two years, including a very active summer 2023 rainy season, many of the island’s shallow and ephemeral wetlands converted back into functional freshwater bodies that many native wildlife species desperately needed.

“Post-Helene, we will be monitoring wildlife in these areas to document their response to brackish water, as well the time it takes to return to freshwater,” he added.